Stack elevator control mechanism for collating machines



M. D. MCSHURLEY STACK ELEVATOR CONTROL MECHANISM FOR COLLATING MACHINES Sept. 18, 1951 Filed Jan. 8l 1949 By M i* H/s Arron/vers M. D. MCSHURLEY STACK ELEVATOR CONTROL MECHANISM FOR COLLATING MACHINES Splt. 18, 1951 8 Sheets-Sheet 2 Filed Jan. 8, 1949 H/` ATTORNEYS Sept 18, 1951 M. QMGSHURLEY 2,568,246

STACK .ELEvAToR CONTROL MECHANISM FOR COLLATING MACHINES l v8 Sheets-Sheet 3 Filed Jan. 8, 1949 H/ A TTOR/VEYS faz nie 17o ml faz M. D. MGSHURLEY STACK ELEVATOR CONTROL MECHANISM FOR COLLATING MACHINES Sept. 18, 1951 a sheets-sheet 4 Filed Jan. 8, 1949 l LI@ lwmci :I llvlllhwllllllu U WIIWHH B s gx 8 Sheets-Sheet 5 ,LJ/S HTTOQNEYS Sept- 18, 1951 M. D. MCSHURLEY STACK ELEVATOR CONTROL MECHANISM FOR COLLATING MACHINES Filed Jan. 8, 1949 Q N, RS

Sept- 18, 1951 M. D. MCSHURLEY STACK ELEVATOR CONTROL MECHANISM FOR COLLATING MACHINES Filed Jan. 8, 1949 8 Sheets-Sheet 6 www MAQS//Au 0. NC 5L/Ua Y lllllll IIIIIH,

HIS HTTOQNEYS sept. 18, 1951 'Filed Jan. s, 1949 M. D. MCSHURLEY STACK ELEVATOR CONTROL MECHANISM FOR COLLATING MACHINES 8 Sheets-Sheet 7 //v vE/voa MARSH/1 L D. Mc SHUEMY B'Ywwfv ,Ll/5 NT TOIPNEYS Sept. 18, 1951 M. D. MGSHURLEY 2,568,246

STACK ELEvAToR CONTROL MECHANISM FOR COLLATING MACHINES 8 sheets-sheet 8 Filed Jan. 8, 1949 www /NVE/v To@ MES/ALL D.

Mc SHI/@LEY HIS T TORNEYS' Patented Sept. i8, 195i i UNITED PATENT o FP1 2,568,246 Y CONTROL MECHANISM FOR CLLTING`MACHINES Marshall -Df-McSll'ily, Muncie,-Ind., assigner to l'General Motors1Go'rporation, Detroit, Mich., a.

corporation yif Delaware pplieafn'liay 8, 1949, Serial N0. 69,925

-3 Claims.

V1 This invention relates to -inachinery'for Stacking storage battery plates and separators in correctorder for assembly.

The rapplication of Poole Aet al., '"Sei'alfNo. 673,574, led May 31, 1946, 'discloses a machine for stacking in correct order all of the 'plates and separators required for `a battery cell. For

example, a machine for stacking the '-plates'and separators for a'cell cfa lgeplate batterywoulld Vhave 37 magazines; By not filling all 'of the magazines of the machine, it can be used-'to Istack `the 'parts for battery cells 'requiringfsm'aller numbers of plates and separators. It is economical to use such a machine where 'the -cguant'itiesbf each battery produced are relatively7 large.

An object of the .present invention is to pro- Yvide a stacking machine for use inthe manufacture of batteries of various capacities where "the quantity production of each item vis 'relatively small. Each battery cell requires a stack'of plate 'and separator parts whose number is `one "plus a vmultiple of four. The disclosed embodiment of the present invention automatically stackselements in groups of four, namely,'a separator,`

apositive plate, 'a separator and a negative plate. Therefore, the requirements o'f each 'cell 'can be obtained by stacking the required number 4cf these groups and placing a negative plate on top of the stack. The machine comprises four 'magazines which receive respectively stacked separators, positive plates, separators and negative plates. Each stack rests `on a platform which is lifted by an hydraulic step-by-ste'p mechanisrn through a distance equal 'tothethickness of vthe'elements in the stack. With eachn'l'agazine, there is 'associated a transfer 'mechanism having vacuum cups which engage the `top element of a 'stack by which the element is'lifted and is then moved horizontally to 'a position 'in which the element is located vertically above an element receiving plate attached to a continuously moving conveyor. The transfer "mechanisrns are operated in timed `relation to the movemerit of the conveyor and theva'cuum vat the 'cups is relieved in time for the elements to drop from the cups upon the plates o'f the conveyor.

The transfer mechanism of thepresentmachine is of the type disclosed 'in the 'Poole application referred to.

It is more particularly an object ofthe 'present invention to provide for the control of hydraulically operated apparatuses for elevating 'the lplatforms o'fthe magazines.

Further objects "and 4advantages "of 'the 'present invention Y'will be apparent frcmlthe 'fllb'wng S55 2 description, vreference being vhad to the accompanying drawings, wherein-a preferred embodi- "me'nt of the present invention is clearly shown.

In the=drawings2 Fig. l is la side view of the frame vof the -rnachine omitting the hydraulically operated maga- 4zines.

'to a larger Vscale than Fig. 6 and taken respectively on lines -1-1, 8--8 and 9 9 of Fig. "6.

Fig. 10 is a sectional view on line mgl-ll Aoi Fig. 6 and is drawn to a larger scale.

Fig. 1l is a View in the directionof arrow H of Fig. io. Fig. v12 is a sectional view on line f2s-l2 of Fig. Y10 and'is drawn to a larger scale.

Fig.. 13 is a sectional view on line l-'SLIB `of Fig. ll and is drawn to the same scale as Fig. 172. Fig '14 is -a sectional View on the line "I 4*-14 of Fig. 1 3.

Fig. 15 is a plan view of one of the "vacuum cup transfer mechanisms. y

Fig. 16 is a view in the direction of arrow I6 of Fig. 15.

Fig. 1 7 is a sectional view on the line ll-2H TF. A15.

Fig. 17A is a view |1A of Fig. 17.

Fig. 18 is a view similar to Fig. l'15 showing the 4transfer mechanism in a different position; Fig. 19 is a'sectonal View von the line lfile-4411) in the direction of arrow of Fig. 18. A

Figs. 20 and 2l are views similar vto Fig. Y19

Vshowing other positions of the transferring l.'tlCl'lal'ls'lfl.

lof Fig. '22, showing a vacuum controlling valve.

Fig. A24 is a sectional view on line 'filer-T24 of Fig. 23.

Fig. 25^is a sectional View on line 5;2'5 df Fig. 24. y

Fig-26, smaller in scale than-"Fig, l22, is *av'i'ew partly in section on line 26-26 of Fig. 22.

Fig. 30 is a sectional View on the line 30-30 of- Fig. 10, showing a plate engaginglatch whereas the corresponding part of Fig. 27 is used for en gaging separators.

Fig. 31 is a diagram of anhydraulic circuit which includes a valve 240..

Figs. 32 and 33 show other positions of valve 240.

Fig. 34 shows a position of `a'reversing valve' 230 different from that shown in Fig. 31.

Referring to Figs. 1 to 6, the machine frame k| attached to a shaft 52 journaled in bearings 53 provided by plates 54, supported for horizontal movement by rails 55 attached to the side frame.

By turning ascrew 56 threaded through a lug 51 integral with a side frame, a plate 54 can be moved for the purpose of taking up the slack in the chain 50 which in Fig. 1 is represented by dotdash lines.

K As shown in Fig. 10, chain 50 passes around ythe driving sprocket 60 attached to shaft 6| which is journaled in bearings 62 supported by the frames 40 and 4| which support angles 63 which support the rails 45. Shaft 6| is connected with,y

a gear 64 (Figs. 6 and 10) meshing with an idle gear 95 pivotally supported by a stud 66 attached to frame 40 and meshing with a gear 61 attached to a shaft jjournaled in bearings 69 provided by frames 40 and 4|. a bevel gear meshing with a bevel gear 1| which, as shown in Fig. 6, is attached to shaft 12 journaled in brackets 13 attached to frame 40. Shaft 12 is connected with a sprocket 14 which a chain connects with a sprocket 15 attached to a shaft 11 which is driven by a motor 80 connected with shaft 11 through a speed reducer contained in a housing 19. The motor and speed reducer are combined in one unit which is supported by a plate 8| supported by the frames 40 and 4|.

Shaft 12 is connected, as shown in Figs. 6 and 8, with a crank arm 82 carrying a pin 63 which a. connecting rod 94 connects with a lever 85 connected withr a shaft 86 journaled in brackets 81 supported by frame 40. Shaft 86 is connected with and supports four levers 88, each connected by a rod 89, turnbuckle 90, rod 9|, pin 92 and ears 93 integral with a plate 94 forming a part of a transfer mechanism designated generally by numeral |00 (Figs. 15-25).

The plate 94 (Figs. 15-17) is attached to rods 95 which pass through holes 96 provided by a carriage 91 which has integral tongues98 (see also Fig. 27) received by grooves in bars 99 sup- Shaft 68 is connected withj 4 a shoulder |05 of the carriage 91 whereby left movement of the rods 95 causes left movement of the carriage, said movement being stopped when the carriage strikes a bar |06 attached to plates |0| and |02. Each rod 95 has a reduced portion which passes through a bar |01 and receives a nut\|08,.the tightening of which clamps the bar Yllagairst a shoulder ofthe rod 95. Bar |01 is connected by rivets |09 with cams ||0 each engageable with a roller which is pivotally supported by horizontal rod ||2 passing through a vertical rod ||3 guided by a bushing ||4 provided by the carriage 91 and connected at its lower end with a plate |5 supporting flexible vacuumcups ||6 and providing ducts, such as ||1 (Fig. 27), by which the cups are connected with a pipe H0 which is connected with a vacuum Ap'urn'p in amanner to be explained later. As

'subjected to vacuum. `movement of lever 88 in a clockwise direction toward the position shown in Fig. 10, the cams I0 "move to the right relative to the carriage 91 to lift the rollers .I and parts supported thereby :intermediate transfer mechanisms Ythree times the center-line spacing of plates 4S.

seen in Figs. 15 and 17, the cams I|l are connected together at the right ends by a spacing pin. and they support a pin 12| on which roller `|2'2'is journaled. Roller |22'rides on a pad.|23 provided by the carriage 91. The rod ||2 which supports the cam engaging rollers supports a roller v| which is engageable with a rail |25 attached to one of the bars 99.

' The position of carriage 91 shown in Fig. 15, is the same as the position of the carriage in Fig. 10 and in that position, the vacuum cups ||6 are vertically above a plate 46 of the conveyor. As the lever 88 movescounterclockwise the carriage 91 moves to the left and into the yposition shown in Fig. 18, in which it engages bar |06. After that, further counterclockwise movement of a lever 88 causes the rods 95 to continue their movement toward the left, thereby causing the cams H0 which are then engaged by the rollers I 'to allow said rollers and the rod ||3 to descend along them as shown in Figs. 20 and 21. The vacuum manifold H5 and cups H6 descend linto the position shown in Fig. 21 so that-the vacuum cups will contact the uppermost ele- ,ment' (either in a separator or a plate) in a magazine below it. At that time the cups are Consequently, during and then the carriage and cams move together to the right while roller |25 rides on track |26.

,When the cups and an element supported thereby have arrived at a location vertically above a con- .veyorplate 46, the vacuum at the cups has been relieved by operation of a valve to be described;

and the element descends from the cups upon a conveyor plate .46. Y

l The centerline spacing of the conveyor plates .or workholders equals the center-line spacing between closely adjacent transfer mechanisms |00 (Fig. 6); and the center-line spacing of the |00 equals The wider spacing between intermediate mechanisms |00 is mainly for the convenience of the attendant who loads the magazines with which the transfer mechanisms are respectively assolciated.,l The motion of lever 88 is so timed to the motion of the conveyor that lever 88 has reached vlthe position shown in Fig. l0 as plate 46 has moved directly under the vacuum cups of the .tubesl with a manifold |3|4 which is either message ling aguide fora 4movable valve sleeve |35 which,

in the Lposition shown Ain V'Fig 125, uncovers a port |36 so that manifold |3| and all the vacuum cups y'of thef'our `transfer mechanisms -are vented. Valve |35 is 'movable between av vertical wall'of Lbracket |3`4 anda coupling nut |31; and, when lagainst thenut |31, valve |35 provides a connection between port |36 and a port |38 sothat manifold |3|"isunvented and is 'connected with 'pi-pe |32. I

" Valve |35 has4 a groove between flanges |39 for receiving pins |40 carried by a lever |4| pivoted ona'pin |42supported`by bracket |34. Lever |4| carries a-rod |43. One 4of the carriages 91 supports -a bracket Mil-having lugs |45 for engaging lever -|4| to move 'it into the position shownin Figs. 23, 24 and 26 by the time the vacuum cups, supported by all the carriages, are vertically above conveyor -plates 46, in consequence of which, the cups release the elements and they `gravitate substantially simultaneously upon conveyor plates 46. As the carriages 91 move right -in Fig. y22 and Vleft in lFig. 10,/a lug |45 of bracket |44 engages the rod |43 to effect counterclockwiseV movement of lever |4| (Figs. 23 and 25)` to veffect right movement of valve sleeve |55 to the 'position for covering port |36 and for connecting it with port |38 so that vacuum will be established at all the vacuum cups.

` lReferring vto Figs. 1-0, l1, 27, l28 and 29, each magazine unit |50 comprisesside plates |5|, |52 4which are secured to aback plate |53. As shown in Fig. l, each back plate |53 is secured to frame 4|. Plates IUI-|02 ofthe transfer mechanism provide continuation respectively of the plates and 52. `In Fig. 1, the letters S designate location of the separator magazines and the letters P the location of the plate maga-- cines. The separator magazine (Fig. 27) includes a-plate |54 which -screws |55 attach to plates |56 and |51, the latter being attached to rod |59 and connected with a piston |59 (Fig. 31) in a cylin- -der-|60 which is supported by the back plate |53. Screws |6| (Figs. l1 and 27) attach to the plate 51, a plate |62 having a slot |63 receiving a lever |64. Lever |64 is engageable with a screw |65 threaded through the lower end portion of plate |62 and secured in the desired position of vadjustrnent of nut |66. Ina manner to be described, the platform |54 which receives separators is elevated intermittently the distance of the f thickness of one separator and when the platform |54 is being elevated a certain distance, thescrew `|95 engages the lever |54 andoperates it'in a manner which causes the piston in cylinder |60 "to move down to lower the platform |54 intoI `position for reloading. Prior to reloading the platform, a stack'of separators is placed upon rollers |"'0'(F'ig. 10) which plates |1|, |12 attach respectively to plates |5| and |52. In orderto 'align `theseparators properly for receptionbe-` V|'1| `or |'12 as 'shown in Fig. 28. As shown in Fig.v

`,29,`the platform of' a plate lmagazine unit is a series of closely spacedrollers |15, journaled in retaient@platelet attaehedfto apiston rod |58.

-In -rder thatthere will fb'efa reserved supply of several elements left adjacent the -vacuum -cups when the platform is lowered for-reloading, Alatch levers |80 (Fig. 21) pivoted on rods IBI (retained by plates' V|82 attached topla-tes |0|, |02) are provided. As the separators move up they engageoblique surfaces |83 of these levers and-spread them apart so ythat there will be sev- -eral separators located Valcove the substantially horizontal portions |84 of these levers.

There- Yfore when -the 'platform |54 is lowered, thesurfaces |5401? levers |90 move under the lastp'latform-supported separator which the platform had carried just before it was lowered. The platform |54 is Jnotched at |54a (Fig. l0) so as to permitthe'levers |60 to'move toward each -other after Ythis-last separator has moved slightly-above the-surfaces |184. No-'springs are required to .returned the levers to the position shown in Fig. 27 because-the centers of gravity of these levers a-resc located as to cause them to return vto normal position -unaided by springs. The plate magazinesV have similar latch levers supported -by pins|9| which are retained by the plates |92 attached to plates |0| and |02. Levers `|96 have obl-ique surfaces |93 and horizontalsurfaces |94 corresponding respectively to surfaces |93 and to provide each with a spring |96 pushing down- |84 of levers |00. In case of the latch levers |90 for the separators, it has been found ydesirable The hydraulic circuit associated with each cyl- Vinder |60 will now be described with reference to Fig. 31. Thereis a main control valve 200 having inlet ports 20| and 202 which pipe 203 connects Iwith an oil .pressure pump and exhaust or drain 'ports 204 and 205 which a vpipe "296 connects with a tank of which the inlet of the pump is connected. There is an outlet port -201 which pipe 206 connects with the upper end of the cylinder' |66 and an loutlet port2l9 `which a pipe 2H) connects with the lower end of the cylinder |60. There is also an outlet port 2H. Avpipe2|2^connects with port 2|3 lof a Valve-229 having ports 2|5 and 2|-6 connected together and `through a balll check valve CV Iwith pipe 2|'. Ports '2|1 and 2|8 are connected together and bypipe 22| with oneend of a metering cylinder Port 2|9 is connected by pipe 223 with the *other* end of saidcylinder. A disc on piston 224 ismovable between theright end of the cylinder 222 and ascrew 225, which is turned by turn- `ing a hand-wheel 226 (Fig. 10) connected with the screw 225 by rod 221 and a coupling 22B.

rfhe movable partofvalve 220`is a disc 230 having passages 23|, 232 located in the same plane and having passages 233, 234 at right angles to 'passages 23| andV 232 and in a plane different able valve member 240 of valve 2|0 has lands spring 244, said upward pressure being commuy jnicated through a clevis 245 to a pin 246 which bars |16 attached to a'"plate |'1`1 which screws' |18 "1l isreceive'dby a notch in lever 241 'attached to ya shaft 24B attached toa lever 249. Spring 244 tends to effect clockwise rotation of levers 241 by a spring 254, said lever having a, hook portion 25| engaging a surface 252 of lever 241.

When the valve 240 is in the position shown .in Fig. 31, pressure fluid will flow from pipe 203 through ports 202, 2li, port 2|3 of valve 220, passage 232, port 2|9, pipe 223 to the left end vof the metering cylinder 222 -thereby causing .right movement of the piston 224 whereby a prethe lower end of the cylinder |60 to cause the piston |59 to be displaced a distance corresponding to the volume of oil which has been included between the piston 224 and the right wall of the cylinder 222. The movement of piston 224 is so adjusted by turning the screw 225 that the piston |59 will lift the magazine platform the dist-ance of the thickness of one element thereon. The apparatus shown in Fig. 31 is the same for the plate and separator magazines. Since the separators are thinner than the plates, the distance between the right end of the screw 225 and the inner wall of cylinder 222 Iwould be less in the case f the separator magazine than in the case of the plate magazine. During each machine cycle which includes a reciprocation of the transfer carriage and a movement of the conveyor workholder plates, the valve member 230 is moved 45 in order to reverse, as shown in Fig.

34, the connections of cylinder 222 with respect to pipes 2|0 and 2|2. As soon as the reversal is made, the metering piston 224 moves left and another increment of hydraulic fluid is forced into the lower end of the cylinder |60. Consequently, by a step-by-step application of a measured amount of pressure fluid, the ystack of elements in a magazine is lifted so that the topmost element is in the stack will be at the proper elevation to be engaged by the vacuum cups of the transfer mechanism. In Fig. 31, arrow A indicates flow of pressure fluid in valve 200 and arrow B, the flow of fluid being forced from the upper end of cylinder |60.

At the time when there are still several elements in the magazine sufficient for a reserve supply during reloading of a magazine, the screw |65 (Fig. 2'1) has been elevated to such height that it will cause lever `259 to move into the position shown in Fig. 32 whereupon the spring 244 pushes the valve member 240 to the position' shown so that the lower end of the cylinder |60 is connected by drain as indicated by arrow C and the upper end thereof is connected with pressure pipe 203 as indicated by arrow D. Piston |59 and the magazine platform supported thereby descends rapidly to loading position. Lever 250 is moved clockwise by spring 254 until its left end engages the surface 255 of the lever 241. The position of lever 249 in Fig. 32 indicates to the attendant that the platform is down for reloading. He reloads the platform and moves the lever 249 to the position shown in Fig. 33, thereby moving the valve member 240 Vto its lowermost position. This causes the upper end of cylinder |60 to be connectedwith drain as indicated by arrow E and the lower end of the cylinder to be connected with pressure pipe v203 ported by the magazine platform and the reserve supply of elements supported by the latch levers |80 or |90. Then the operator releases the lever 249 and the spring 244 returns thevvalve 240 to the position shown in Fig. 31, 4the hook 25| of lever 250 again engaging the surface 252 of lever .shaft 248.

In case it is desired to move lever 249 into the position shown in Fig. 32 without waiting for lever 250 to be moved into unlatched position automatically, the operator will push down on a button 21|) (Fig. 13) against the action of a restoring spring 21|, thereby moving downwardly a rod 212 and a bar v213 to cause it to engage a plate 214 attached to shaft 253 and to effect counterclockwise movement of lever 250. As shown in Fig. 14, the shaft 248vhas a square portion 215 received by a square hole in the lever 249 which is retained by nut 215` threadedly engaging an end portion of shaft 248. The bar 213 has an elongated hole 213a which receives the shaft 248 which therefore limits the movement of bar 213. Bar 213 is retained alongside the lever 249 by the head of a stud 211 attached .to lever 249 and having a shank portion received by an elongated hole 218, of bar 213. As shown in Fig. 11, the shaft 248 is journaled in bearings provided by plates |1| and |12. A spacer 219 (Fig. 12) is located between the plate |12 and the bar 213. The shaft 253 is journaled in a bearing provided by plate 280 attached to plate |12 and in a bearing provided by a plate 28| which receives the shaft 248 and a screw 282 which, as shown in Figs. 12 and 31, passes through ears 283 provided by valve 200 and is retained by nut 284. The plate 28| establishes a definite location between the centers of shafts 248 and 253 and the screw 282 and therefore a definite location of valve 200 relative to the As shown in Fig. 10, valve 200`is secured to a plate 285 which is supported by plates |5| and |52.

The four reversing valves 220 and metering cylinders 222 of the four magazine units are shown in Fig. 6.` There are four brackets 290 attached to frame 40, each supporting reversing valve 220 and metering cylinder 222. Each valve member 230 (Fig. 31) is connected with a shaft 29| to which is attached a beveled gear l292 (Fig. 6) meshing with bevel gear 293 attached to a shaft 294. Shaft 294 is turned intermittently 45 by a mechanism which includes a lever 295 (Fig. 10) connected with the shaft 86 connected by an adjustable link 296 with a lever 291 which, as shown in Fig. 7, is pivotally supported by shaft 294. Lever 291 carries a pin 298 pivotally supporting a pawl 299 which a spring 300 urges against a ratchet 30| attached to shaft 294. Lever 291 will be moved down from the position shown in Fig. '1 suciently for the pawl to drop behind a ratchet tooth while a retaining pawl 302 prevents counterclockwise rotation of the ratchet. Pawl 302 is supported by a pin 303 attached to a bracket 299 and urged counterclockwise by a spring 304. The upward movement of the lever 291 is sucient to cause 45 clockwise rotation of ratchet 30|. Hence the four reversing valves are indexed simultaneously while the four transfer mechanisms are carrying elements from the magazines to workholder plates ofthe conveyor. Therefore 'by the time these elements have dropped upon the conveyor plates, the magazine platformsl will have been elevated distances equal to ther thickness of the elements vsupported thereby.'

From the foregoing description, itis apparent that the present machine l 'provides a" conveyor and transfer mechanism-'operating inY timed relation, magazines each having ai platforni fsupporting a stack of elementsand'v anhydraulic servo'for raising the pl'atf'orr'n,"eachA servo being controlled for step-by-step elevat-Ienof' the plat'- fo'rm by a main control valve inconjunction with a pressure fluid metering devi-cey whichli's vcontrolled by a reversingvalveI operated in"`timd relation to the transfer mechanismf lin response to elevation of the' vplatfornfrfa predetermined distance; the main l"control valve' isfoperated automatically to` causethe servo tolower the plat'- form for reloading. The` main controlvalvecan be manually operated for' this purpose without IWaiting for automatic operation to takeplace. The main controlvalve is `inaniially operated for the purpose of causing'`l the lservo to lift the loaded platform so that the uppermost element of the stack ,thereonengages theV lowermost element of the reserve supply. at the top of the magazine.

While the embodiment of the present invention as herein disclosed, coifistitut'es apreferred form, it is to be understood that other forms might be adopted. l Y. f What is claimed Yis as follows;

Ait

1. A machine for stacking ydifferent partisiin-'a certain order comprising a plurality of magazines A each having a vertically movable platformiupon which a stack of like partsisfplac'ed, a-'conv'eyor,

'part holders moved thereby, transfer devices each operative to cause the uppermost part on a stack to be transferred to a holder, a mechanism for effecting movement of .the holders by the conveyor and operation of the transfer devices in timed relation whereby, during each cycle of operation of the machine, the parts are transferred to positions to be received by the holders as the holders are located by the conveyor to receive the parts, a plurality of pressure fluid operated servos for raising and lowering the platforms, each servo comprising a piston connected with a platform and a cylinder into one or first end -of which pressure-fluid is admitted to effect raising -the platform and into the other or second end of which pressure-fluid is admitted ytoeffect lowering the platform, a rst controller for each servo for passing a -predetermined quantity of pressure-fluid from a pressure-fluid sourc e"`to the first end of the cylinder to effect elevation of the platform a distance equal to Ithe thickness of the parts thereon, a mechanism operated by the first mechanism for causing operation of the first controller once during each cycle of machine operation whereby the platform is elevated by step-by-step movement, a by-pass around the first controller to the rst end of the cylinder, a second controller including a valve having a movable element having three positions, namely, an intermediate position which conditions the valve for connecting the first controller with a fluidpressure source and the second end of the cylinder with drain, one end or second position which conditions the valve for connection of the first end of the cylinder with drain and the second end of the cylinder with the pressure source so that -the platform is lowered and another end or third position which conditions the.

valve for correction of the pressure source with the by-pass to the first end of the cylinder and the other end of the cylinder with drain so that lment-toward second position; a manually oper- "in response to elevation of the platform to a certain level for retracting the latch to permit the spring `to move the valve from intermediate to second position, to effect lowering the platform,

manually controlled means for retracting the latch to effect lowering' of the platformwhen ',desired, said lever being manually operated to causthe valve element to move to intermediate position or past intermediate position to third position., release of the lever permitting said spring to Amove the valve from third to intermediate position in which it is retained by said latchj' and means in' each magazine and located adjacent to the transfer device associated therewith-for retaining a'nuinb'er of parts sucient to 'supply the transfer device while the platform of the magazine isl lowered, loaded and raised.

2. A machine' for stacking different parts in a certain order comprising a plurality'k of magazines 4each `having a vertically movable ,platform upon which a stack of like parts is placed, a conveyor, means for. moving the conveyor, a: plurality of part holders alaptedy to be moved by the conveyor, a plurality of transfer devices each operative to cause the uppermost part on a stack Q t'o be`v transferred to a part holder, a' mechanism for effecting movement of the i part holder'sby the conveyor and operation of the transfer devices in timed relation whereby, during each cycle of operation of the machine, the parts are transferred to positions to be received by the part holders as the holders are located by the conveyor to receive the parts, a plurality of -pressure fluid operated servos for raising and lowering said platforms, a controller for each servo having means for causing application of a predetermined quantity of pressure fluid to the servo to cause it to raise a platform a distance equal to the thickness of the parts thereon, contr-ol mechanism operated by the rst mechanism for causing timed operation of each 0f said control means once during each cycle of machine operation whereby each platform is elevated by a stepby-step movement upon each cycle of operation, a second group of controllers for said servos for causing operation thereof independently of said first controllers,I means associated with each magazine for holding a small supply of parts at upper limiting position adjacent the transfer device during reloading of the platform, includthe platform is raised independently of control ing pressure-fluid by-passes respectively around the rst controller and manually operated means Y associated with each of said second controllers for admitting pressure fluid through a by-pass to the servo to eifect upward movement of the platform in order to lift the stack of parts placed thereon into contact with parts retained whereby normal step-by-step operation of the platforms is reinstated.

3. A machine for stacking different parts in a certain order comprising a plurality of magazines each having a vertically movable platform upon which a stack of like parts is placed, a conveyor, means for moving the conveyor, a plurality of part holders adapted to be moved by the conveyor, a plurality of transfer devices each operative to cause the uppermost part on a stack to be transferred to a part holder, a mechanism for effecting movement of the part holders by the conveyor and operation of the transfer devices in timed relation whereby, during each cycle of operation of the machine, the parts are transferred to positions to be received by the part holders as the holders are located by the conveyor to receive the parts, a plurality of pressure iiuid operated servos for raising and lowering said platforms, a controller for each servo having means for causing application of a predetermined quantity of pressure fluid -to the servo to cause it to raise a platform a distance equal to the thickness of the parts thereon, control mechanism operated .by the rst mechanism for causing timed operation of each of said control means once during each cycle of machine operation whereby each platform is elevated by a stepby-step movement upon each cycle of operation, a second group of controllers for said servos for causing operation thereof independently of said first controllers, means operatively connected with each magazine for retaining parts at the upper portion thereof adjacent the transfer device to supply it during reloading the platform, pressure-fluid by-passes, respectively, around the first controllers for each of said second con-` trollers and having a movable element with three positions, namely, an intermediate position which conditions said second controller for admission of pressure fluid to the first controller, a second position on oneside of intermediate position which conditions the second controller for cessation of ow of pressure uid to the first controller and for admission of pressure fluid to the servo -to cause it to lower the platform, and a third position on the other side of intermediate position which conditions the second controller for admission of pressure-duid through a by-pass to the servo to cause it to raise the platform, a spring for each second controller urging lthe movable element from intermediate to second position, a latch normally operating to prevent; movement of the element from intermediate position, to second position, means responsive to elevation of the platform to a certain level for retracting the latch whereby the element is moved by the spring from intermediate to second position, and a manually operable means for moving the element through intermediate position to third position, release of said manually operable means permitting return by said spring of the element from third to intermediate position in which the element is retained by the latch.

MARSHALL D. MCSHURLEY.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 794,146 Ericson July 4, 1905 2,137,381 Blackstone Nov. 22, 1938 2,247,466 Baker et al. l July 1, 1941 2,295,055 Rupp et al. Sept'. 8, 1942 2,435,915 Williams Feb. 10, 1948 2,479,060 Davidson Aug. 16, 1949 

